Heart failure (HF) is a major and growing public health problem in the United States. Approximately 5 million patients in this country have HF, and over 550,000 patients are diagnosed with HF for the first time each year. Heart failure is the primary reason for 12 to 15 million office visits and 6.5 million hospital days each year.
Heart failure is a complex clinical syndrome that can result from any structural or functional cardiac disorder that impairs the ability of the ventricle to fill with or eject blood. The cardinal manifestations of HF are dyspnea and fatigue (which may limit exercise tolerance) and fluid retention (which may lead to pulmonary congestion and peripheral edema). Both abnormalities can impair the functional capacity and quality of life of affected subjects.
Heart failure may result from disorders of the pericardium, myocardium, endocardium or great vessels, but the majority of patients with HF have symptoms due to an impairment of left ventricular (LV) myocardial function. LV myocardial dysfunction begins with some injury to, or stress on, the myocardium and is generally a progressive process, even in the absence of a new identifiable insult to the heart. The principal manifestation of such progression is a change in the geometry and structure of the LV, such that the chamber dilates and/or hypertrophies and becomes more spherical, a process referred to as cardiac remodeling. This change in chamber size and structure not only increases the hemodynamic stresses on the walls of the failing heart and depresses its mechanical performance but may also increase regurgitant flow through the mitral valve. These effects, in turn, serve to sustain and exacerbate the remodeling process. Cardiac remodeling generally precedes the development of symptoms (sometimes by months or even years), continues after the appearance of symptoms, and contributes substantially to worsening of symptoms despite treatment.
Accordingly, methods and kits for detecting early cardiac remodeling in subjects without clinical signs of heart failure are highly desirable, especially in subjects at risk such as obese subjects.